I had the same problem with the Accel coil that came with my Notch. Didn't care for it much, and since the stock TFI system is good for 50kV, I bought a new stock replacement. No probs since. I didn't see how something buzzing under my hood was doing much for me anyhow, other than making me worry if it was going to explode or something.
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Capri306, Moderator, The Mustang Works Online
1979 Mercury Capri, 5.0L -- C4 -- 2.73
1987 Mustang LX Notch 
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